The Role of Percutaneous Coronary Intervention in the Treatment of Chronic Total Occlusions: Rationale and Review of the Literature

Dilemmas in cardiology: when to recanalize a chronic total occlusion

The decision whether or not to recanalize a chronic total occlusion (CTO) of a coronary artery is truly a dilemma for the cardiologist. The procedure is in fact complex, with a non-negligible rate of complications and with a probability of success lower than that of non-obstructive lesions. The analysis of the data available in the literature, with the significant discrepancy between the results of the randomized studies and the observational studies, does not currently allow conclusive statements on the role of the percutaneous coronary interventions in CTO. It is therefore essential to incorporate clinical, anatomical and procedural elements into the decision-making algorithm. While awaiting new randomized clinical trials of greater dimensions and better methodology, a careful selection of patients is certainly essential, limiting the procedure to those who are symptomatic or who have a high ischaemic burden and excluding those who have no evidence of vitality, without which it is not legitimate to expect any benefit from the intervention. Finally, the presence of the collateral circulation does not in itself appear to be an element that should have a significant decision-making role.

Angiographic Characteristics and Outcomes of Percutaneous Coronary Intervention of Reattempted Chronic Total Occlusion: Potential Contributing Factors to Procedural Success

This study aimed to analyze angiographic characteristics of new attempted percutaneous coronary intervention (PCI) on chronic total occlusion (CTO) compared to first attempt group. The cohort of 527 CTO-PCIs was divided into first-attempt and re-attempt groups, and angiographic characteristics, level of complexity, and contributing factors to failure were analyzed. Between-group success rate difference and potential angiographic and technical aspects contributing to the success in new attempts were scrutinized. A total of 47 new PCIs in 39 patients were performed. The reattempt group showed higher J-CTO score compared to the first-attempt group (2.4 ± 1.06 vs. 1.2 ± 1.06; p < 0.001). The use of more complex techniques and devices such as retrograde approach (29.8% vs. 12.9%) and IVUS (48.9 vs. 27.3%; p: 0.002) were more frequent in the reattempt group. Both procedural and fluoroscopy time were higher in the reattempt group (197 ± 83.9 vs. 150.1 ± 72.3 and 97.7 ± 55.4 vs. 68.7 ± 43, respectively; p < 0.001). There was no between-group difference in terms of technical success (79.8 vs. 76.6% for first attempt vs. reattempt group, respectively; p: 0.6). The overall success rate increased by 6.1%, achieving 85.9% in the entire cohort. Reattempted CTO-PCIs required more complex techniques and had comparable technical success rate with regard to the first-attempt group.

Long-Term Outcomes of Percutaneous Coronary Intervention for Patients With In-Stent Chronic Total Occlusion Versus De Novo Chronic Total Occlusion

Limited data are available on long-term outcomes and health status in the treatment of in-stent coronary chronic total occlusion (IS-CTO) and de novo coronary chronic total occlusion (de novo CTO). This study compared the long-term clinical outcomes and health status of percutaneous coronary intervention (PCI) for patients with IS-CTO versus patients with de novo CTO in the drug-eluting stent era. We screened 483 consecutive patients with 1 CTO lesion, including 81 patients with IS-CTO and 402 patients with de novo CTO. Propensity score matching was used to balance baseline characteristics between the 2 groups. The clinical end point was major adverse cardiac events (MACE). The success rates of CTO lesion revascularization were similar in both groups. In the propensity score-matched patients, after a median follow-up of 36 months, MACE was observed in 32.8% of patients with IS-CTO versus 13.5% of the patients with de novo CTO (P < .001), mainly driven by target-vessel revascularization (21.9% vs 6.7%; P < .01). Moreover, patients with IS-CTO had significantly worse Seattle Angina Questionnaire anginal stability scores than the patients with de novo CTO. In conclusion, patients with IS-CTO after PCI had a worse clinical outcome, mainly MACE, and a poorer anginal stability in the long term than patients with de novo CTO.

Management of Chronic Total Occlusion of Coronary Artery

Chronic total occlusion (CTO) of a coronary artery is typically defined as a completely occluded artery without any antegrade flow and a duration of at least 3 months. We reviewed the current literature describing the optimal management of CTO including the role of revascularization and choice of modality, i.e., percutaneous coronary intervention (PCI) or coronary artery bypass graft surgery. Databases (PubMed, the Cochrane Library, Embase, EBSCO, Web of Science, and CINAHL) were searched and relevant studies of patients with CTO were selected for review. The prevalence of coronary artery CTOs is approximately 25% among patients undergoing coronary angiography for angina. Available data suggests that PCI of CTO can be a technically complex procedure with relatively lower success rates compared with non-CTO PCI and typically associated with a higher complication rate especially at nonspecialized centers. Furthermore, successful CTO-PCI is associated with symptomatic improvement but does not appear to improve mortality, myocardial infarction, stroke, and repeat revascularization rates. Based on contemporary data, PCI of CTO lesions may be considered in patients with incapacitating angina despite treatment with optimal guideline-directed medical therapy and in whom based on coronary anatomy there is a reasonable chance of technical success with an acceptable risk.